Purpose
Financial resources for health care are limited, so assessment of intervention effectiveness in terms of health in relation to its costs is important. Measuring health outcomes in cost-effectiveness analyses is usually done by health-related quality of life measures, like the EQ-5D. However, over the past decade, innovations on the conceptual level of health have evolved and novel approaches are rising such as the capability approach, subjective wellbeing, and Positive Health. This study assesses the psychometric properties of the subjective wellbeing-5 dimension (SWB-5D) outcome measure.
Methods
A quantitative, cross-sectional study design was used to determine the concurrent and construct (convergent and known group) validity for the SWB-5D. Concurrent and convergent validity were estimated as correlations between the SWB-5D and the Dutch version of the EQ-5D, ICECAP-A, and PH-17. Assessment of known-groups validity was based on the variables illness, education, and the overall happiness (Cantril Ladder) and overall health scale (EQ-5D VAS).
Results
A representative sample of 1016 respondents of the Dutch population completed an online questionnaire. The SWB-5D showed reasonable concurrent validity and showed good convergent and known-group validity. The SWB-5D had a lower ceiling effect compared to the EQ-5D and ICECAP-A.
Conclusion
Compared to traditional health measurement approaches, novel approaches are more focused on the mental and social pillars of health. The SWB-5D shows psychometric feasibility of comprehensive measurement of health, as indicated by a range of validity measures in a large representative sample of the Dutch population.